Flux for galvanizing



mama on. as, test; Zfitfit UNITED STATES PATENT orrica FLUX FORGALVANIZING Raymond J. Kepfer, Lakewood, Ohio, assignor,

by mesne assignments, to E. I. du Pont de Nemours & Company, Wilmington,Del., a corporation of Delaware No Drawing. Application November 14,1934, Serial'No. 752,943

6 Claims. (Cl. 91'l0.2)

This invention relates to flux compositions Also, since the flux andfoaming agent are intiand processes for hot dip galvanizing, and ismately mixed and in proper proportions, there is particularly directedto prepared flux composino charring of foaming agent.

tions and to processes wherein a protein, or pro- The compositions of myinvention are com- I tein containing material, is used as a foamingposed of a protein and a chloride flux selected 5 agent from the groupconsisting of zinc chloride, am-

In hot dip galvanizing, a bath of molten zinc monium chloride, and zincammonium chloride. is covered with a flux. As articles to be gal- Theprotein is added as a protein containing vanized are lowered into themolten zinc bath, material, as it is unnecessary and impractical to 10they, of course, first pass through the flux where use a pure protein.10 they are cleaned and prepared for the reception While I may use anyprotein, I prefer to employ of a metal coating. a protein material fromthe group consisting of It has heretofore been the practice to add acotton-seed meal, gelatine, glue, albumen, diastomaterial such asglycerine or tallow to the flux for, and and milk powde Generally, Iprefer on th molten bath, in order to produce a foam to use aprotein-material of animal origin as 15 or froth. This foam serves toentrap vapors and such materials are particularly eflicient and aregases, and to retard the rate of volatilization of well adapted to my pp 0118 Protein the flux. In the course ofa galvanizing operaterial ofvegetable origin, cotton-seed meal, is tion, it has been necessary toreplace such of the q te efl e as a foaming t. y reason flux as hasvolatilized, and it has also been necesof its low cost and its stabilitywhen stored with 20 sary to add foam producing material to maina flux,it is one of my preferred materials. tain.a foam blanket of the desiredthickness and While I usually employ from about one to five character.per cent of a protein material, the amount rz-ay A considerable loss offlux and of foam probe widely varied according to the conditions ofd'ucing agent resulted from the fact that they use and according to theamount and type of 25 were added separately, and at the judgment ofimpurities which the protein material contains. the galvanizer. At timesthere was not enough When the composition is to be used in a basketofthe foaming agent present to maintain a foam p cess, or in a DIOCBSSSimilar type, it is of proper consistency and thickness, with thesirable to maintain a thick, heavy foam. Comresult that an excessiveamount of flux was lost positions to be used with such processes shouldby volatilization. At other times, and especially contain about threeper cent, or more, of a proimmediately following its addition, there wastein material. present an excess of poorly mixed foaming ma- 'However,in the so-called hook process in which terial, with the result that someof it was de: articles are suspended from hooks when lowered 5 composedand charred by the high temperatures into the bath, it is necessary touse a somewhat of the galvanizing pot. In addition to thus wastlighterand thinner foam as otherwise thearticles ing foaming agent, thisdecomposition and charwill not penetrate the foam, but will float offring resulted in the formation of charred parthe hooks and becomedetached. For this type ticles which interfere with the galvanizing opofprocess the flux composition preferably con- 40 eration. tains fromabout one to three per cent of protein 40 It is an object of thisinvention to provide material. processes and compositions whereby anoptimum As typical examples of compositions according foam thickness andconsistency are easily mainto my invention, I may give the following:tained, and whereby there is a minimum loss of Example 1.A prepared fluxparticularly flux and foaming agent. A further object of my adapted foruse in a basket-type galvanizing proc- 45 invention is to provide aprepared composition ess was prepared by intimately mixing three perwhich may be conveniently and easily used. cent of cotton-seed meal witha zinc ammonium Other objects will appear hereinafter. chloride flux(44% ZnClz and 56% NH4C1) This I accomplish my objects bymixing togetherth composition was used by adding some of it directproper amounts of aflux and a protein containly to a galvanizing pot containing moltenzinc. 50 ing material. A galvanizer is thus enabled to add An excellentfoam blanket which lasted about the flux and foaming agent convenientlyand in thirty-six minutes and which was about five the proportionsrequired to obtain a desired inches thick was obtained. It was easilymalnheight and consistency of foam. As a result, tained by adding moreof the composition as there is no excessive loss of flux byvolatilization. needed. 55

Example 2.A similar flux composition was prepared using five per cent ofcotton-seed meal. A foam seven inches thick which lasted aboutthirty-nine minutes was obtained.

Example 3.-A flux composition particularly adapted for use in ahook-type galvanizing process was prepared by intimately mixing one andone-half per cent of cotton-seed meal with a zinc ammonium chlorideflux. With this prepared composition, a foam about three and one-halfinches thick was obtained. The foam lasted about thirty minutes, and itwas then necessary to add more of the prepared composition to maintainthe foam. The foam was of a relatively thin consistency, and whenarticles suspended from hooks were lowered into the bath, theypenetrated the foam without floating oil the hooks.

Example 4.-A composition similar to that of Example 3 was prepared usingtwo per cent of cotton-seed meal. A foam which lasted about thirty-fiveminutes and which was about four inches thick was obtained.

Example 5.A prepared flux composition was made by mixing two per cent ofgelatine with a zinc ammonium chloride flux. Using this composition in agalvanizing pot, there was obtained a foam eight inches thick whichlasted over twenty minutes.

Example 6.A similar composition using one per cent of bone glue produceda foam five inches thick which lasted about twenty minutes.

The gelatine of Example 5 is, of course, .very similar in its action tothe glue of Example 6 since gelatine is a refined form of animal glue.When I refer to animal glue hereinafter, it will be understood that theproduct may be of any degree of purity.

In addition to the agents above listed, albumen, diastofor (a maltextract), and milk powder may be mentioned as examples of proteinmaterials which I have found satisfactory for the purposes of myinvention.

The protein materials above noted contain some substances other thanproteins. The foreign substances make it necessary to add a largerweight of material, but they do not seriously interfere with theoperation of the materials as foaming agents, and there is no particularneed to remove them. If desired, of course, the proteins may be purifiedby removing some, or all, of the foreign materials.

The foaming agents may be mixed with the flux in any desired manner. Forinstance, the foaming agent in finely divided form may be tumbled orground with the flux.

While the invention, as above described, is particularly adapted to hotdip galvanizing, it may be applied to other hot dip processes. It

may, for instance, be applied to processes of hot dip coating which usemolten baths of tin, lead, or cadmium.

While I have disclosed certain specific compositions and processes, theyare merely illustrative and I do not intend to be limited thereby, thescope of my invention appearing from the following claims:

I claim:

1. As a new article of manufacture, a foaming galvanizing fluxcomposition for use on a galvanizing bath of molten metal, comprising apredetermined amount of a protein material of animal origin and achloride flux selected from the group consisting of zinc chloride,ammonium chloride, and zinc ammonium chloride.

2. As a new article of manufacture, a foaming galvanizing fluxcomposition for use on a galvanizing bath of molten metal, comprising apredetermined amount of animal glue and a chloride flux selected fromthe group consisting of zinc chloride, ammonium chloride, and zincammonium chloride.

3. Ass new article of manufacture, a foaming galvanizing fluxcomposition for use on a galvanizing bath of molten metal comprising apredetermined amount of albumen and a chloride flux selected from thegroup consisting of zinc chloride, ammonium chloride, and zinc ammoniumchloride.

4. In a process of hot dip galvanizing wherein articles to be coated areimmersed in a bath of molten zinc, the steps comprising adding directlyto the bath a foaming flux comprising a predetermined amount of aprotein material of animal origin and a chloride flux selected from thegroup consisting of zinc chloride, ammonium chloride, and zinc ammoniumchloride, and maintaining a desired foam character and thickness bydirectly adding more of the foaming flux as required.

5. In a process of hot dip galvanizing wherein articles to be coated areimmersed in a bath of molten zinc, the steps comprising adding directlyto the bath a foaming flux comprising a predetermined amount of animalglue and a chloride flux selected from the group consisting of zincchloride, ammonium chloride, and zinc ammonium chloride, and maintaininga desired foam character and thickness by directly adding more of thefoaming flux as required.

6. In a process of hot dip galvanizing wherein articles to be coated areimmersed in a bath of molten zinc, the steps comprising adding directlyto the bath a foaming flux comprising a predetermined amount of albumenand a chloride flux selected from the group consisting of zinc chloride,ammonium chloride, and zinc ammonium chloride, and maintaining a desiredfoam character and thickness by directly adding more of the foaming fluxas required.

RAYMOND J. 60

